Under total cardiopulmonary bypass, a model of transposition of the great vessels is made in dogs by the construction of an intra-atrial baffle. The transposition complex is then corrected at the great vessel level by constructing a truncus arteriosus utilizing the proximal segments of the aorta and pulmonary artery and distal aorta. The pulmonary blood flow is then established between the left ventricle and distal pulmonary artery by means of an extra cardiac shunt.